Helge Klein has posted part three of his series where he used UberAgent to measure the impact of certain factors on Logon Performance - which is one of the most crucial success factors in traditional End User Computing. This time it is about WMI filters.

Group Policy offers four ways to control where the settings defined in a Group Policy Object (GPO) are applied:

Organizational units (OUs)

Group user/computer objects in OUs

Link GPOs to OUs

Security

Change GPO security so that the GPO applies to specific groups

Required permissions: read + apply group policy

Works not only for users, but also for computer accounts

WMI filters

Specify a WMI query

The GPO is applied only if the query returns true

Applies to entire GPOs

Item-level targeting (ILT)

Specify targeting criteria

A setting is applied only if the criteria match

Applies to individual settings (in case of registry settings: can also apply to a collection of settings)

Available for Group Policy Preferences (GPPs) only, not for Policies

Out of these four, two are interesting in terms of performance: WMI filters and item-level targeting. We are going to dedicate the rest of this article to them.